Interlocking plug-switch.



Q m M .vR In N n m A r A. R. SMITH. INTERLOGKING PLUG SWITCH. APPLIOATION FILED sum 21. 1904 RTHUR 1 1 (I/ZZ whom it ntay concern:

Be it known that I, ARTHUR B. SMITH, a citizen of the, United States, residing at is possible to insert two plugs in such a man that a second plug cannot be inserted therein.

thimble. a

The sccl ts are supported on the back or p panel ulating material, in which are ing both the holes, and adapted to receive a I flanged escutcheon 4, containing two holes i being preferably provided with a flanged {of N ew York, have invented certain new and fuseful Improvements in Interlocking Plug- Switches, of which, the following is a specification,

'terminals to bra-connected. Such switches R.iSMIT H, OF SCHENECTADY,

ELECTRIC COMPANY, A CORPORATlON OF NEW YORK.

r ng A m inn-3n. v

NEW Your, ASSIGNOR ro GENERAL ENTERLQQWNQ; PLUG SWlTQH.

n ssenso.

Schenectady; countyof Schenectady, State This invention relates toswitches for electric'circuits, and especially to those in which the circuit is closed by inserting a plug of conducting material into a socket containing are used in central stations to connect feeder bus-bars with any phase of a two-phase or. three-phase circuit, especially when it is desired to change the circuits fed from any given machine. It is evident that when a system of single plug-switches provides for connecting any bus-bar with any circuit it nor as to connect the same circuit with both terminals of the same generator, thus short-- My invention aims to prevent the possibility of such anaccident. I accomplish this by arrangingthe blocks the entrance to the other socket, so

The invention is also applicable to any situation Where a given conductor is to be connected with either one of two other con ductors, but not with both at once.

In the accompanying drawings, Figure l is a side elevation. liig. 2 is a top plan view. Fig. 3 is an elevation of the terminal supporting-panel, showing the recess for? -e escutchecn; and F 1g. 5 is arrow of the spht l ig. 'fl is a frontelevation of a pin tics drilled twc holes 2 2. A recess 3 preferably made the front of the panel, includregistering with the holes 2 2". A. metal tube 5 extends through each of said holes.

front end, which is clamped against the lace of the escutcheon by a 5 with external screw-threads on the rear portion or Specification of Letters Patent. Application. filed September 21, 1904. serial No: 225.311.

Patented Dec. 25, 1906.

the tube behind the panel. Between the nuts and the panel is inserted a metal plate 7, having a terminal 8 secured thereto. The plate has forkedends to. straddle the tubes and lie under the nuts. 1

The end of the. tube5 at the backof. the panel is attached by a um'on 9 to-a tube 10, of insulation, in alinement with the tube a bar 11, of insulation, suitably supported on brackets 12, fastened to the panel. A sleeve 13 is securedto the'tube 10 and hasan out-' wardly-projecting flange which "rests against. a shoulder surrounding an opening in a' Atits rear end the tube 10 passes through i handle lSjattached to a tube 19, of metal,

adapted to slide easily into the tubes 5 10 and having a solid tip 20 to enter and make contact with the thimble 15. In order to insure good metallic contact between the plug and the tube 5, a split thimble 21 issecured in the tube 5 and hugs the tube 19 when the latter is thrust into the socket. The operation is'as follows: inasmuch the sockets are arranged with their mouths close together, but diverging from other, it follows that when a plug is inserted into one of llllfiillsay the hole 2"-as shown in Fi 1. thereby closing the circuit between the and the clip 17 at the end of the l which the plug has been inserted, the handle of the plug stands across the hole 2, so that second plug cannot be'thrust into the other socket or even entered therein. The device thus rendered fool-proof" and er of accidental sl1ort-circuiting by closing switches at once is effectually prevented.

While t.

' 1 =7 shown only two sockets, yet it is evi ...nll the lnvention is applicable to a plural cl them in case it is desired to cut 11' airy one and only oneof several branch at apparent that the invention may be he to be restricted .to the specific cl in erious forms, and I therefore,

form 5' own and described, but intend to cover b the claims all changes and modifies tLons which are within the-s rit and scope of my invention.

What I c aim as new, and desire to secure byLettrs i atent t the United States, is-

1. A switch comprising a plurality of sockets which intersect if prolonged, and contactplugs for said sockets extendingwhen in 0perative position beyond the point of intersection of the prolongations of the sockets,

whereby the insertion of one plug prevents the insertion of another plug into an adjacent socket. A

2. A switch comprising a plurality of switch-sockets and a contactplug formed to intersect the axes of the other switch-sockets when inserted in one of them.

3. A switch comprising a plurality of sockets intersecting when prolonged, and contact-plugs extending beyond the point of intersection when in operative position.

4. A switch comprising a suitable support, sockets mounted thereon so that said sockets when prolonged intersect near said sup ort, and contact-plugs extending beyond sai point of intersection when in operative position.

5. The combination With a supportin panel having adjacent holes, of a plug-switc comprising sockets mounted adjacent said holes in such position that said sockets intersect when prolonged, and contact-plugs extending beyond the point of intersection when in operative position whereby the insertion of one plug prevents the insertion of another.

6. The combination with a supportingpanel having two adjacent holes, of metallic tubes extending through the same, a terztinal plate adjacent to said tubes, nuts on said tubes clamping said plate to the panel, and terminals insulated from but in line withsaid tubes. I

In witness whereof- I have hereunto set my hand this 19th day of September, 1904.

ARTHUR B. SMITH. Witnesses BENJAMIN B. HULL, HELEN Onronn. 

